1. Field of the Invention
This invention relates to irrigation systems. More particularly, it relates to devices for adding liquid fertilizers, insecticides, herbicides, fungicides and the like to the water distributed by an automatic sprinkler system.
2. Description of the Related Art
The availability of low-cost PVC pipe and solvent-welded PVC pipe fittings has resulted in the widespread installation and use of automatic sprinkler systems. Such systems typically comprise a source of fresh water under pressure (often a community water utility), a manifold for distributing the water into various zones each having a plurality of sprinkler heads, a series of electrically-actuated valves for controlling the flow of water in each of the zones, a timer for opening and closing the valves at pre-selected times or time intervals, and a backflow prevention device for keeping possibly contaminated water from re-entering the supply system.
An in-ground, automatic sprinkler system presents the opportunity to conveniently distribute water-soluble chemicals such as fertilizers, weed killers, fungicides, and insecticides to areas served by the system. A number of United States patents concern devices for adding water soluble chemicals to sprinkler and irrigation systems.
U.S. Pat. No. 7,011,254 to Thornton describes a lawn chemical application system that comprises a dispenser having a lower chamber, an upper chamber, an upstream opening, and a downstream opening. The dispenser may be formed by a tee connector and a cylinder secured to an upper opening of the tee connector. Powered valves are operably connected to the upstream and downstream openings of the dispenser. The powered valves may be wired to open and close simultaneously. A lower portion of the upper chamber may be disposed below an upper portion of the lower chamber and above a lower portion of the lower chamber, leaving the lower portion of the lower chamber unobstructed over substantially its entire length. The lower portion of the upper chamber may have a plurality of openings to provide for adequate mixing of water with the chemicals stored in the upper chamber. In operation, soluble matter or other chemicals are placed in the upper chamber of the dispenser, and the two valves are opened simultaneously. Water flows through the first powered valve and into the dispenser, where the water is mixed with soluble matter or other chemicals stored in the upper chamber of the tee. The solution or mixture then passes from the dispenser, through the second powered valve, to one or more sprinkler heads of the irrigation system. When the application is finished, the valves are closed simultaneously.
U.S. Pat. No. 6,997,350 to Johnson et al. describes an apparatus for adding liquid fertilizer to a water line of a sprinkler system. The apparatus includes a mechanical injector device powered by a paddle wheel turned by water flowing through the water line. The mechanical injector device includes a plunger that moves back and forth in the plunger chamber. Movement in one direction allows liquid fertilizer from a liquid fertilizer reservoir to flow into the plunger chamber and movement of the plunger in the opposite direction injects the liquid fertilizer from the plunger chamber into the water. The mechanical injector device is coupled to the paddle wheel which causes movement of the plunger in the plunger chamber in at least one direction. Spring bias can cause movement of the plunger in the other direction. The mechanical injector device can be disabled to stop fertilizer injection while still allowing rotation of the paddle wheel. The paddle wheel is coupled to the mechanical injector device through a plunger gear which rotates, and interacting camming surfaces which project from the plunger gear and from a ratchet.
U.S. Pat. No. 6,969,011 to Palmer describes a chemical additive dispensing device for use with a station of a sprinkler-based irrigation system that includes a fluid diversion housing and a container for storing a chemical additive. The fluid diversion housing includes an in-flow channel formed therein that is in fluid communication with an input port and the container. An out-flow channel is also formed within the fluid diversion housing and is in fluid communication with an output port and the container. In operation, the container fills with fluid from the in-flow channel such that the fluid mixes with the chemical additive. Once the container is filled with fluid, the mixture of fluid and chemical additive is diverted through the out-flow channel of the fluid diversion housing to the outlet port such that the fluid chemical additive mixture is distributed to the rest of the irrigation system and particularly through sprinklers onto a lawn and/or plants.
U.S. Pat. No. 6,942,128 to Walter describes an automatic dispenser for underground sprinkler-systems. The unit is placed before the zone valves of the sprinkler system. The unit is designed to disperse fertilizer into a tank chamber below a discharge tray. The fertilizer dissolves in the water and is distributed/dispersed to the appropriate sprinkler system zone. The discharge tray has multiple chambers based on the number of zones in the sprinkler system. The chambers in the discharge tray can hold various capacities based on the area covered by each zone within the sprinkler system. The discharge tray turns to dispense the fertilizer as the sprinkler system changes from zone to zone. The discharge tray is automatically moved. The chambers are manually refilled based on the frequency of yard fertilization. The unit has an access from the top to the discharge tray for filling chambers with fertilizer material.
U.S. Pat. No. 6,722,583 to Restaino et al. describes a lawn sprinkler accessory with a hollow body defining a chamber for holding lawn treatment material, such as fertilizer, herbicide or insecticide. The accessory body has a hollow water inlet arm on one side and a hollow water outlet arm on the opposite side of the chamber. An access opening with a removable closure in one end of the accessory body enables the insertion of lawn treatment material into the chamber and its removal from the chamber.
U.S. Pat. No. 6,540,156 to Martin describes a fertilizer and irrigation apparatus that includes an inflow pipe, a shunt pipe connected to the inflow pipe, and a chemical additive assembly connected in parallel to the shunt pipe. An outflow pipe is also connected to the shunt pipe. A portion of the inflow pipe, the shunt pipe, the chemical additive assembly, and the outflow pipe are all above ground. The chemical additive assembly includes a quantity of a chemical additive. A manifold is connected to the outflow pipe. A plurality of in-ground distribution conduits are connected to the manifold, wherein each of the distribution conduits includes at least one above-ground sprinkler head. In addition, an auxiliary inflow assembly can be connected to the inflow pipe so that chemical additives can be supplied to the fertilizer and irrigation apparatus from an outside source.
U.S. Pat. No. 6,267,303 to Francis describes a sprinkler system fertilizer injector that comprises a device for injecting liquid chemical solutions into the flow of a lawn sprinkler system. The device is said to allow the user to easily attach and remove chemical jars without the risk of losing the prime on the pump.
U.S. Pat. No. 6,206,046 to Finley describes a lawn and garden chemical dispensing system that employs an I.V.-style collapsible bag as a water flow controlled dispenser of liquid or water-soluble beneficial chemicals for sprinkling systems. The system consists of a stand, a chemical vessel, a vessel sleeve, a vessel cap with dual port (internal/external) bulkhead union, an optional filter attachment, a chemical feed tube, and a control valve tap connected to a water flow supply.
U.S. Pat. No. 6,173,732 to Davis et al. describes a chemical feeding system for adding either liquid or 100% water soluble solid chemicals including fertilizer, insecticide and a herbicide to a lawn sprinkler system either above or below ground level. The system has one or two vertically oriented mixing chambers containing a removable sponge filter. An effluent tube is attached to the bottom of the mixing chamber for recycling through an adjustable flow meter valve. A drain tube with a shutoff valve and a one-way check valve leads to the main sprinkler system.
U.S. Pat. No. 5,836,518 to Jester describes a fertilizer sprinkler system including a pipe system adapted for flow of liquid therethrough. The pipe system is comprised of an open inboard portion, a closed outboard portion and an intermediate portion. The inboard portion is coupled to a main water line. The intermediate portion is defined by a first vertical member, a horizontal member and a second vertical member. The intermediate portion further has a lower horizontal member having a first end in fluid communication with the first vertical member and a second end in fluid communication with the second vertical member. The lower horizontal member has an intermediate segment having an integral lid extending downwardly therefrom. The lid has an inlet port and an outlet port therethrough. A fertilizer container removably couples with the lid of the pipe system. A plurality of outlet valves are positioned within the outboard portion of the pipe system. The plurality of outlet valves are adapted for coupling with sprinklers.
U.S. Pat. No. 5,366,159 to Childers describes an automatic fertilizing apparatus which injects fertilizer directly into the water stream of a sprinkler system. Each time the sprinkler system is activated, a predetermined amount of fertilizer is dispensed into the water stream. The apparatus can be controlled to dispense fertilizer only thru sprinkler lines determined by the user.
U.S. Pat. No. 5,364,030 to Murdock et al. describes a solution injector for underground sprinkler systems comprising an intake pipe connected with a bypass pipe at a system inlet pipe “T”, a tank, and an outflow pipe connected at one end to the tank and at the other to the bypass pipe. The intake pipe is connected to the tank through an intake valve and an intake hose, and the solution injector further comprises a bypass valve installed on the bypass pipe between the system inlet pipe “T” and the system outlet pipe “T”.
U.S. Pat. No. 5,303,729 to DeMarco describes An automatic fertilizing device for introducing lawn care chemicals such as fertilizer, herbicides, insecticides, and fungicides into a sprinkler system, comprising a container having a control plate insert to divide the container into an upper and lower volume. The container and control plate are mounted to a flow head, such that the flow head controls the amount of chemicals drawn from the container and dispersed into the main water line.
U.S. Pat. No. 5,199,645 to Anderson et al. describes a conversion kit for converting an existing sprinkler system liquid supply line into a general purpose soluble chemical application device is used to apply insecticides or fertilizer. The easily installed kit mixes dry chemicals with an existing pressurized liquid to form and expel appropriate treatment solution. Spent dry chemicals can be easily replaced in a removable canister. Chemicals from conventional bulk packages or specially prepared packets may be used. A safety interlock shutoff valve is provided to prevent pressurization of the system while chemicals are being replaced. A vacuum breaking air vent valve is provided to allow drainage of liquid from the system. All components are enclosed within and supported by a single housing.
U.S. Pat. No. 5,178,181 to Craig describes an applicator for use with a sprinkler line system. The applicator comprises a fertilizer container with integrally formed internal inlet and outlet tubes. Water is fed through an inlet-outlet tube into the bottom of the fertilizer container, where it dissolves or dilutes some of the solid or liquid fertilizer and forms a leached, concentrated solution. This concentrate continuously rises through the fertilizer and into the outlet tube where it drains downwardly. The concentrate is then diluted with water coming through the inlet-outlet tube including a venturi, the size of which controls the flow rate of the concentrate. The diluted concentrate is then passed into the sprinkler system for application to vegetation. The bore arrangement of the applicator enables the device to be drained and then filled with fertilizer, followed by running water through the fertilizer at a selected time. This is said to render the operation more automatic.